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gfast map nov

Dark Green: Firm commitments from incumbent: BT (10M), Belgacom, Australian NBN, Swisscom,  Austria, Bezeq Israel, Chunghwa Taiwan, Telus Canada, Telekom South Africa, SK Korea, (U.S.) AT&T, Century, Frontier, Windstream, Belgium, Omantel

Mid Pink: Smaller carriers in Germany, Norway, Finland, Japan

Light Green: Incumbent likely:  France, Germany, Italy

British-Telecom-noise-dataBT thinks the current G.fast is too conservative and the standard needs to be changed for more performance. Gavin Patterson is telling the government BT is going to deliver a gigabit. He's arguing BT shouldn't be broken up because BT is building "the best network in Europe." But his best network is running at 330 megabits while cable around the world is going to a gigabit. Comcast is about to offer a gigabit to 40 million homes. 

The order came down from the top: make it faster. The same thing is happening at AT&T. They've promised 12M lines of "GigaPower," much of which will be G.fast. But it's not a gigabit. So AT&T is leading the move for a new standard with more speed.

BT Openreach's latest update lists key developments they expect will increase speeds:

  • Increasing the maximum aggregate transmit power from 4dBm to 8dBm
  • Increasing the number of bits per tone from 11 to 15 
  • Improved use of the frequency band below 30MHz
  • Optimised frequency usage with VDSL2 
They, like many others, want to raise the limit of vectored connections from today's 16 homes to 48 or higher.
 

Ikanos's Arun Hiremath is optimistic they can deliver what BT is asking. For short loops, Ikanos is designing to 1.2 gigabit speed. These design changes should also help longer loops. Arun sees better analog engineering as crucial.

BT's decision earlier this year mostly to use existing cabinets changed the focus of the industry. Most important now  is long loop performance rather than high frequencies that don't reach very far. Non-linear precoding is necessary in the higher frequencies but not as vital at lower frequencies with reach. With no carrier interested in going to 212 MHz, coding improvements are on the back burner. 

 

BT Openreach's latest update lists key developments they expect will increase speeds:

  • Increasing the maximum aggregate transmit power from 4dBm to 8dBm
  • Increasing the number of bits per tone from 11 to 15 
  • Improved use of the frequency band below 30MHz
  • Optimised frequency usage with VDSL2 
They, like many others, want to raise the limit of vectored connections from today's 16 homes to 48 or higher

The Site for gfast 230
 

G.fast News

I’m still working through remarkable presentations from the Broadband Forum events. Michael Weissman, Bernd Hesse and team did a remarkable job choosing the speakers. http://bit.ly/BBFBASE

Deutsche Telecom: 35b Supervectoring Delayed to 2019 http://bit.ly/35blater
Broadcom is now over 3 years late. DT briefed German reporters after their financial call and revealed 35b was now delayed until 2019. 35b should deliver 200+ meg downloads 500-600 meters, a crucial tool for DT, which is losing share to cable. Cable now covers about 70% of Germany and is expanding. DT now only offers 50-100 megabit DSL while cable is often 400 megabits, going to a gigabit. 

The problem is software; the hardware is shipping and supposedly will work. DT says 35b is not ready to turn on. Broadcom in 2015 said 35b was in "production" in the press release below. Alcatel in early 2016 said to expect complete systems very soon. "35g is very similar to 17a so there should be little delay."

Broadcom's problems are leading major telcos and vendors to have a plan B, using Sckipio G.fast. DT itself is planning extensive G.fast deployments in 2019, mostly in apartment buildings. http://bit.ly/35blater

Gigabit 100 Meters - Unless the Wires are Lousy http://bit.ly/gflousy
Speeds are fine, "Unless there's a line problem." I've been reporting for three years that ~10% of lines have problems. In the chart by Rami Verbin of Sckipio, he finds G.fast goes ~130 meters on good lines. Poor lines have about half the reach. 

His chart roughly matches the reports from Swisscom, Belgacom, and England for both G.fast & vectored DSL. The 10% with problems can cause the majority of the line-related complaints to support. The angry customers drive up cost.

Rami's solution to reach the gigabit is bonding, supported on the Sckipio chips. Verbin made some additional points:

  • 4 gigabits is possible by bonding two decent 2 gigabit lines.
  • Even in a service from remote cabinets, ~25% are close enough to get a full gigabit."
  • cDTA and iDTA are practical ways to deliver much higher upstream by switching some bandwidth from downstream to upstream only when needed.
  • 35B will probably be similar but Deutsche Telecom doesn't expect to deploy until 2019. http://bit.ly/gflousy

AT&T Wants Coax 2-5 Gigabit G.fast. Very Soon. http://bit.ly/ATTCoax
AT&T faces intense competition from cable, talking about 10 gigabits in both directions. (Cable will only be 1 gig down, ~100 meg up, until ~2021.) AT&T wants something to brag about as well.

AT&T gained millions of lines of coax as part of the DirecTV deal. Alcatel and Huawei are leading the development of G.mgfast. That uses 424 MHz, full duplex, to achieve ~2.5 gigabits in both directions. The reach on telco twisted pair is only about 30 meters. On coax, those speeds can probably extend far enough to service most apartment buildings. Using 848 MHz, speeds can reach 5 gigabits. The ITU standards group has been aiming for 2019-2020 for G.mgfast, too slow for AT&T's marketers. David Titus wants a high-speed standard for coax "early in 2018." He believes that is "doable."http://bit.ly/ATTCoax

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